<?php
/**
 * Simple function to replicate PHP 5 behaviour
 */
function microtime_float()
{
	if( PHP_VERSION > 5){ 
		return microtime(true); 
	}else{
		list($usec, $sec) = explode(" ", microtime());
		return ((float)$usec + (float)$sec);
	}	
}

$time_start = microtime_float();

// Sleep for a while
usleep(100);

$time_end = microtime_float();
$time = $time_end - $time_start;

echo "Did nothing in $time seconds\n";
?>